It is well recognized that proper and uniform seed spacing in the furrow is essential to maximizing crop yield. In order to achieve this proper and uniform seed spacing in the furrow, virtually all commercially available seed meters for row-crop planters are designed to singulate seeds, i.e., to dispense individuals seeds at regular intervals.
Presently, commercially available seed meters can generally be divided into two categories on the basis of the seed selection mechanism employed, namely, mechanical or pneumatic. The most common commercially available mechanical meters include finger-pickup meters such as disclosed in U.S. Pat. No. 3,552,601 to Hansen (“Hansen '601”), cavity-disc meters such as disclosed in U.S. Pat. No. 5,720,233 to Lodico et al. (“Lodico '233”), and belt meters such as disclosed in U.S. Pat. No. 5,992,338 to Romans (“Romans '338”). The most common commercially available pneumatic meters include vacuum-disc meters such as disclosed in U.S. Pat. No. 3,990,606 to Gegenhan (“Gugenhan '606”) and in U.S. Pat. No. 5,170,909 to Lundie et al. (“Lundie '909”) and positive-air meters such as disclosed in U.S. Pat. No. 4,450,979 to Deckler (“Deckler '979”).
As with all equipment, the parts of a seed meter will eventually wear over time. Worn parts may effect the seed meter's ability to uniformly singulate the seeds. For example, due to worn parts, the seed meter may fail to consistently dispense seeds at regular intervals, thereby resulting in seed “skips.” Alternatively, the worn parts may occasionally cause two or even three seeds to be dispensed at one time, resulting in seed “doubles” or seed “triples,” respectively. Such seed multiples, as with seed skips, will effect the uniformity of seed spacing in the furrow and ultimately decrease crop yield.
In addition to worn parts, planter speed, seed population, different seed sizes, and different seed shapes will effect the ability of a seed meter to uniformity dispense individual seeds at regular intervals. As such, successful farmers recognize that they must not only regularly inspect and replace worn parts of their seed meters, they must also calibrate or adjust their seed meters depending on the desired or target seed population and the seed type and/or seed variety to be planted. For example, when switching between different seed types or seed varieties, the seeds may vary in size from small to large and the seeds may vary in shape from round to flat, etc. While a seed meter may be perfectly adjusted to singulate small round seeds at a desired seed population, upon switching to a large round or large flat seed variety, the seed selection mechanism may not be able to consistently select the larger seeds, resulting in excessive seed skips. As a further example, when increasing seed population, the higher rotational speeds of the seed meter's seed selection mechanism may prevent consistent seed selection and/or seed retention, thereby also resulting in excessive seed skips. As a further example, the seed meter's brushes or seed strippers may be set too aggressively for larger seeds or the increased rotation speed of the seed selection mechanism, also resulting in excessive skips. In yet a further example, upon switching to small flat seed variety, the seed selection mechanism may select and retain multiple seeds and the meter's brushes or strippers may not be set aggressively enough to consistently remove or strip the excess seeds from the selection mechanism, thereby resulting in excessive seed multiples being dispensed by the meter.
Accordingly, it should be appreciated that there is a need for an apparatus and method for testing a seed meter's ability to singulate seeds whereby a farmer can use such test results to properly calibrate or adjust the meter to minimize seed skips or seed multiples when planting a particular variety of seed at a desired or target seed population. The seed meter testing apparatus disclosed in U.S. Pat. 5,938,071 to Sauder (the “Sauder '071 patent) is directed toward such an apparatus and method. The Sauder '071 patent is hereby incorporated herein by reference.
As disclosed in the '071 patent, a seed meter desired to be tested is removed from the planter and mounted to the testing apparatus. In operation, the variable speed motor is engaged to operably drive the flighted belt and to operably drive the seed meter's seed selection mechanism at the desired rotational speed to achieve the desired or target seed population or seed discharge rate. The seeds with which the meter is desired to be tested is supplied to the seed meter by an operator. The seed meter dispenses the seeds in its normal mode of operation onto the moving flighted belt. After a predetermined number cells of the flighted belt pass (which directly corresponds to the target seed population), the belt and the meter are stopped and the seeds on the belt are counted. If the seed meter is properly adjusted or calibrated and operating properly, the number of seeds actually dispensed on the belt should equal the target seed population. In addition, the operator can count the number of skips (i.e., empty cells) and multiples (i.e., cells containing more than one seed) to determine the number or “errors” in that “run” of cells. From this error count, the operator can then easily calculate the accuracy of the seed meter's performance in terms of percent singulation, i.e., the number of instances in which an error occurred in a run divided by the number of cells in that run and multiplying the quotient by 100. Other relevant statistical data can also be calculated based on the error count and known number of cells comprising a run, including the percentage of skips in the run, the percentage of multiples in the run, etc. This process is generally repeated two or more times to obtain a more accurate average error percentage for the meter being tested. If the error percentage is deemed excessive, appropriate adjustments can be made to the seed meter, as recognized by those skilled in the art depending on the seed meter type. This testing and adjustment process is repeated until the meter is properly calibrated to dispense seeds at the desired seed population and to singulate the seeds within acceptable error percentages for the particular seed variety and seed population desired.
While the apparatus and method disclosed in the Sauder '071 patent effectively meet and satisfactorily serve the purposes and the functions for which they are intended, a more efficient apparatus and method of testing a seed meter is desired that does not require the operator to stop the belt to identify the meter's accuracy and singulation efficiency. Accordingly, it is desired to provide an apparatus and method for testing seed meters that offers the features and advantages of the apparatus disclosed in the Sauder '071 patent, but which is more efficient in operation by automating the seed count and error detection operations without having to stop the belt, and by displaying to the operator other desired or relevant information about the accuracy of operation and efficiency of the seed meter being tested.